Pipeline embolization of MCA aneurysms in the M2-M4 segment: Dual center study and meta-analysis

Objective: Flow diversion of distal MCA aneurysms in the M2-M4 segments with Pipeline embolization device is promising, but further study is needed. Here, we seek to quantify the safety and efficacy of Pipeline embolization in the M2-M4 region in a dual-center cohort and comprehensive meta-analysis. Methods: Clinical and angiographic data of eligible patients was obtained from participating centers. A systematic review was performed with searches of Pubmed, Scopus, Embase, and the Cochrane Library for articles from inception to May 2021. 86 studies were identified in systematic review. Of these, 7 studies with 46 aneurysms met the inclusion criteria and were aggregated with 8 aneurysms from our dual-center cohort for analysis. Results: In our dual-center cohort, complete occlusion was observed in 88% (7/8) of aneurysms, and no patients experienced hemorrhagic or thromboembolic complications. Clinical outcomes were reported for 100% (54/54) of aneurysms included in meta-analysis and angiographic follow-up was available for 91% (49/54). The overall rate of complete aneurysm occlusion was 80% (95% CI, 69-91%), and the overall rate of clinical complication was 9% (95% CI, 2-16%). Conclusion: Pipeline embolization of cerebral aneurysms of the M2-M4 segments of the MCA was reasonably effective and safe in a small group of selected patients, but further study is needed to validate these preliminary results.

Automated summary

This study aimed to evaluate the safety and efficacy of Pipeline embolization for distal MCA aneurysms in the M2-M4 segments. The results showed that Pipeline embolization achieved a high rate of aneurysm occlusion (88%) with no clinical complications in our dual-center cohort. The meta-analysis demonstrated an overall aneurysm occlusion rate of 80% and a clinical complication rate of 9%.